Played by Keri Russell. Felicity is the main character of the show. The series opens with Felicity's high school graduation. She intends to attend Stanford University and study pre-med. A sudden change of heart, after a conversation with her high school crush, leads her to abandon those plans and go to New York University instead. Once there she quickly realizes that she needs to find herself, away from her parents' sometimes overbearing influence and expectations. She begins her freshman year as an intelligent and thoughtful yet extremely impulsive person; however, as the show progresses, she grows into a more secure and centered young woman.

Played by Scott Speedman. Ben is the initial reason Felicity moves to New York. Like Felicity, he moved from Palo Alto, California to New York. Upon seeing Felicity in New York, Ben patiently accepts a barrage of romantic interest from Felicity, though he and Felicity's singer-songwriter best friend Julie share a mutual attraction to one another. Ben and Julie start a relationship mid-way into his freshman year that lasts for a few months. He also becomes a protective and loyal friend to Felicity. At the end of freshman year, Ben suffers a brief gambling addiction, and serious financial issues that threaten his tuition and livelihood. He is not a strong student but is athletic and is especially good at swimming. Ben and Felicity begin a relationship in summer before sophomore year, which they maintain on-and-off again throughout the series. (Their relationship is a central feature of the show, even catalyzing time travel.) During one of these off-times, in sophomore year, he has a strung out affair with a married caterer named Maggie, who is vindictive of her philandering husband. Senior year, Ben impregnates his father's AA sponsor Lauren. Ben's home life is complex. While his father (played by John Ritter) is an alcoholic and continually makes promises only to break them, Ben's mother continues to stay with her husband. Ben has difficulty expressing his feelings and initially appears not to be very thoughtful or contemplative (especially in contrast to Felicity). He often makes hasty or detrimental decisions that he later regrets. However, throughout the series, Ben's true depth and sensitivity are revealed.

Played by Scott Foley. Noel first appeared in the show as Felicity's sophomore Resident Advisor. Felicity often vents to him about her unrequited love interest Ben; this creates internal conflict for Noel as he romantically pursues Felicity. Noel also has a long-term, long distance girlfriend named Hanna (Jennifer Garner) who is a composer. They break up on Thanksgiving after Hanna reveals that she is spending time with a man at her college. Noel begins dating Felicity that very day. They experience stumbling blocks along the way, namely Noel's conflicted feelings for ex-girlfriend Hanna, and when Felicity in turns loses her virginity to an art student (Simon Rex). They break up after a few months when she chooses a summer road trip with Ben over Noel's invitation to Berlin. But Noel entertains the notion of a romantic relationship Felicity for the rest of the series. He moves into a two-bedroom apartment at the onset of his junior year and roommates with Elena. His tension with Felicity eases to the point of affection. Noel meets Ruby, a freshman advisee and dorm-mate to Felicity. Ruby is a new actress vying for the romantic lead opposite Tom Cruise in a blockbuster film. She gets the part. Noel and Ruby maintain a long-distance set-up while she's on location, with regular visits. Noel ends the relationship after two or three months when he learns that Ruby is pregnant with a child who is not related to him. In the summer between Junior and Senior years, Noel drops out of college, gets highlights and marries Javier's cousin, Natalie (Ali Landry). He is eventually talked down by his friends and associates, re-darkens his hair and annuls the marriage. Noel is a self-identified computer geek with a particular fondness for Mac computers and graphic design. Noel comes from a working-class background and has one older brother whom he looks up to as a model guy complete with the ideal girlfriend. Unbeknownst to Noel, his brother (Eddie McClintock) is gay. He comes out to Noel in the first season, and asks for support in sharing this with their parents.

Played by Tangi Miller. Elena is Felicity's first lab partner and also lives on Felicity's floor in the dorm. She is from New York and prior to University she lived with her widowed father. Her mother died of cancer when she was "very young." Elena is from a working-class background and her tuition is paid through scholarships. She is a fiercely competitive and driven student with plans to attend medical school. She appears more confident and direction driven than Felicity, but, as they become closer, she opens up and reveals some her own insecurities. Elena has a few romantic relationships through the course of the show. She dates Blair, a fellow student, for the first half of her freshman year until Felicity catches Blair and Elena's best friend in an affair. After seeing the two for herself, Elena ends the relationship by punching Blair in the face. These events bring Elena and Felicity closer together as friends. Later that year, Elena embarks on an affair with her much older professor, Dr. McGrath. She volunteers to fill in for his assistant in the evenings and the two develop a relationship after a string of flirtations. Later it becomes apparent that she is only one of several students he has cunningly seduced. Elena's most significant relationship is with Tracy, a virgin. They become engaged but ultimately do not marry. Elena is killed in a car accident in season four, but remains alive in alternate timeline due to Felicity's spontaneous time travel.

Played by Amy Jo Johnson. Julie is Felicity's first real friend at UNY. She is a guitar player and singer/songwriter. Julie has a mutual attraction with Ben, Felicity's main love interest and impetus for moving to New York. Julie is flirtatious by nature and often finds herself in uncomfortable situations involving men. During first year she dates a film student, who goes on to date rape her. Around this time, she finds comfort and patience in Ben who supports her through the emotional aftermath in late night conversation and sleepovers. They date halfway into freshman year for a few months. At the end of that year, Ben uses the "heavy" tone of the relationship as a reason to break up. Julie later finds out that Ben was interested in Felicity. Also in the first season, it is revealed that Julie has come to New York to find her birth mother. Julie hires a private detective who finds her. She then applies for an internship at her birth mother's firm in order to learn more about her. Julie finds that the two have much in common, including a talent for rhythm guitar. Eventually, she confronts her mother with her identity, and after the initial shock they form a warm dialogue. Julie later finds out that her mother's current husband is actually her birth father. She was conceived when they were teenagers and her mother gave birth to Julie unbeknownst to her father. The two reconnected in college, were married and had two more children. Julie's birth mother fears being exposed and is more than hesitant to introduce Julie to her father. Sophomore year, Julie moves into Sean and Ben's apartment. She places a greater focus on her music and turning it into a career.

Played by Greg Grunberg. Sean is not a student at UNY with everyone else. He is in his mid to late twenties and owns his own loft apartment. Ben is roommates with him during the first season and subsequently, Julie, Meghan and Noel all live there at some point. He doesn't appear to have a job throughout the series (until the end), but is constantly coming up with new entrepreneurial ideas. A partial list includes: marzipan boxers (edible), disposable camera vending machines, Lacto’s milkless cereal (just add water), Bagel knobs – injected w/ cream cheese and lox, etc., Shreme (sugar and cream), Flavored pen caps, Marshmallow rotisserie, Smoothaise (a condiment of unknown ingredients), Shrimp yogurt, ‘Before and After’ – a restaurant that only serves appetizers and desserts, Sleep mask alarm clock combo, Comfort cologne – smells like guys’ favorite foods - mac and cheese, brisket, lasagna, etc. and Shoe covers. In season 2, he and Meghan Rotundi begin dating and in season 4 they, rather impulsively, get married.

Played by Amanda Foreman. Meghan is Felicity's first roommate during her dorm days. She is a goth wiccan and appears to be the polar opposite of Felicity, whom she describes living with as "like living with a TV that's always playing Little House on the Prairie, only with more sweaters." Initially she and Felicity fail to see eye-to-eye on things, but by the end of the series Meghan and Felicity have formed a very close and lasting friendship.

Played by Ian Gomez. Javier is Felicity and Ben's manager at Dean & DeLuca, a coffee shop. He is from Spain, speaks in a strong Spanish accent and is animated and bubbly. He becomes very close with both Felicity and Ben and, through them comes to know Elena, Noel and Julie. He has a boyfriend, Samuel and they get married at the end of season two. He also decides to go back to school and get his degree beginning in season three.